Two thirds of doctors and dentists who attended a pioneering scheme run by the National Health Service to rehabilitate sick medics were suffering mental health disorders while the rest were addicted to alcohol and "every drug under the sun", the GP leading the programme said today.

In its first year more than 180 medics used the Practioneer Health Programme (PHP), set up to help medics grappling with the stress of long hours as well as the stigma of illness and addiction in the profession. The vast majority of cases were doctors who were clinically depressed or suffering from alcoholism.

Of those with addiction problems about one in four were hooked on drugs, the rest were dependent on alcohol. Clare Gerada, the programme's medical director highlighted cases of addiction to "ketamine, methadrone, amphetamine, heroin... every drug under the sun." Unlike normal addicts, it appeared doctors would not imbibe while at work such was their concern for their patients but would binge when off-duty.

Almost one in three of those reporting mental health issues had depression, about a fifth suffered from anxiety attacks and a third had a condition such as an eating disorder. Alarmingly Dr Gerada said in six cases there had been an "undiagnosed psychosis... bipolar disorders where doctors were working but nobody had picked up the illness... obviously with (this programme) we were able to pick it up much earlier before they were able to damage patients".

The programme, the brainchild of the outgoing chief medical officer Sir Liam Donaldson, was set up in London in September 2008 as a belated recognition that doctors do not always have the same access to healthcare as their patients. The problem was often doctors would try to "manage their own condition rather than seek help".

The programme offers a confidential service to get doctors back into work and the figures released yesterday showed it had managed a 77% success rate. It is likely to be replicated in other parts of the country starting with Newcastle and Avon.

In a sense the breakthrough is a wider acceptance that doctors get ill and need help as patients, said Dr Gerada. "The problems are complex but there's a feeling that is wrong that doctors do not get sick... they also don't seek help or treat themselves. Patients could be harmed if doctors go untreated."

Thanks to a campaign to promote the programme, run from a south London GP clinic, officials said PHP had become the largest of its kind in the world. "In Canada a similiar service had 11 patients, in Poland they had 9... the service destigmatizes (the process)," said Professor Alastair Scotland, medical director of the National Clinical Assessment Authority.